Vesticon will develop a Stimulus-Evoked Vestibular Evaluation System (SEVE) for detecting and analyzing sound/pressure-evoked manifestations (Tullio/Hennebert phenomena) of conditions causing dizziness or imbalance for application at medical facilities. Such conditions comprise a significant proportion of all disorders resulting in complaints of dizziness/imbalance. In all, dizziness and imbalance disorders chronically affect 6.2 million Americans, where balance-related falls account for more than half of accidental deaths in the elderly. Although treatment for most of these conditions is available, diagnosis poses a significant sorting problem due to diverse causes and symptoms, requiring advanced technology to assist in the detection and analysis. Current technology for analysis of stimulus-evoked phenomena is limited to single-function, difficult-to-operate, non-interpretative products, which are neither comprehensive nor time-efficient. SEVE will automate diagnostic and localizing tests for the Tullio and Hennebert phenomena that are well known in the literature, but are often discounted, performed incorrectly or not at all due to practicality, and a lack of standardization and training. Components for presentation of sound and pressure stimuli, and components for vector analysis of the nystagmus response and quantification of head/body postural responses, will be combined and automated with interpretative and clinical decision support software. During Phase I we will: (a) adapt a head-worn apparatus containing spatial orientation and motion sensors, goggles with infrared cameras and a body-worn wireless subject-console for transmission of stimuli and response data; (b) develop a computer-controlled ear stimulus system with sound and air pressure stimuli; (c) develop software for interpreting stimulus-response data to determine and display quantified evidence of vertigo; (d) bench-test the SEVE system and (e) demonstrate the value of SEVE in a small subject cohort with vertigo, and assess user friendliness. For Phase II, we anticipate engineering modifications, enhancing software for diagnostic protocols, interpretation, integrative analysis for decision support, and demonstrating improved applications with a large subject population at the Pl's clinic and 2 independent beta sites.